300gr SMK in Shilen 338 Edge

[Northerner]

My brother found a 338Edge on Gunbroker and since I have the loader and 100yd range at my house, I have the gun now breaking in the barrel and trying to find a load it likes. The barrel and action are Shilen. The stock is a big heavy synthetic of some kind. The barrel is 32" long with a big brake. Seems like all the pieces are there for a good shooting rifle. The magazine on the gun will only take 3.650" COL. I have tried 89 - 93gr of H1000 and have not seen a group under 1.25". A lot of vertical strings, two shots very close, touching most often, and one 1.25 - 1.5" high. Each grain of powder has increased velocity about 35fps. I am not seeing any pressure signs at 93gr and a velocity of 2805fps. I decided to load some longer than the magazine to get closer to the lands. I loaded 91gr of H1000 at 3.873". Still a group about 1.38" and velocity of 2806fps.

Do the SMK's want to be seated very close to the lands? Will they jump the .225" and shoot okay? If I can get them to shoot will jumping .225" hurt anything?

Any ideas would be great.

 

[littletoes]

The biggest determining factor is O-jive, and since SMK's are Tangent o-jive, and not secant o-jive, they are much more forgiving to "jump" than secant.

Good Luck out there!

 

[varmintH8R]

If you can make them shoot, I wouldn't worry about the jump.

Maybe try some Retumbo - a little slower burn in that half-mile barrel!! Should be a sweet shooter once you get her tuned in. You may also want to move back to 200yds - I was told by another LRH'er that the big 338's seem to settle in at 200+. I was skeptical, but have found it to be mostly true....

 

[Northerner]

I have tried 91 and 92 gr Retumbo with similar vertical groups of 1.25 - 1.50" Velocity was better than with h1000 and no pressure signs. I am trying to find some RL-25 to see what it will do.

I don't understand the vertical groups. It does seem like it is the same shot each time. I have been shooting 3 shot groups and the high one has been any of the three with no consistency as to which one.